By Caroline Ryan
BBC News Online health staff
The mysteries of how the brain controls everything from language to movement could be explained by a "map" created by scientists.
Everyone's brain is different
The international team behind the atlas used thousands of images of the brains of people of all ages, and with a range of conditions.
They hope to create the most comprehensive picture yet of the brain's structures and functions.
They have carried out brain scans on 7,000 people to obtain the data needed to create the map, and they say they will continue to add to the atlas as more research is carried out.
Scientists from six countries have been involved in putting the atlas together.
They hope the data will tell them more about which areas of the brain control specific functions in the body.
They also hope to be able to find out more about how the brains of people with particular conditions such as Alzheimer's disease or schizophrenia differ from healthy brains.
The brain map could help them spot the early signs of disease, they say.
Word of the map spread quickly between neurologists around the world, and clinics sent images to the team compiling the database, which now holds thousands of images.
Everyone's brain is different, a different shape and size and organised differently.
The only way to understand how the brain works, say experts, is to gather information from as many scans as possible, in an attempt to establish what an "average" brain looks like.
Dr John Mazziotta, an expert on the imagery of the human brain from the University of California, Los Angeles, (UCLA) said: "No two brains are the same. Their shape. Their size. The way they are organised.
"You can't just point at an area and say, 'Here's the seat of language'.
"For example, the brain handles the challenge of thinking and initiating a word, and of understanding that word differently.
"Execution of these tasks involves complex circuitry throughout the brain."
Arthur Toga, professor of neurology at the UCLA, who also worked on the map, told BBC News Online: "There was no way to compare or contrast that information without a comprehensive map of the brain.
"Now we have compiled this database, this atlas.
"We can now look at the information in different forms so you can look at different aspects of how the brain works."
He said there were many possibilities for how the information could be used.
"We might be able to stratify the data on the basis of gender, or by disease.
"For example, the signature of Alzheimer's disease changes over time. It's a degenerative disease which has an increasing effect on the brain.
"We know what an Alzheimer's brain looks like, but what we really want to do is find out what a Alzheimer's brain looks like before the disease manifests itself.
"That could allow doctors to begin treatment early."
He added: "The most important thing is to have an applicable general database against which we can compare disease populations."
But the team's work was not finished.
"We want to have an understanding of the brain that's more comprehensive than we have now," he said.
The images are courtesy of the Laboratory of Neuro Imaging, at the David Geffen School of Medicine, UCLA.